package JCT_Chapter_03;

import static java.lang.Character.getType;

public class LotteryArray {
    public static void main(String[] args){
        /**
         * This program demonstrates a triangular array
         */
        final int NMAX = 10;
        // allocate triangular array
        int[][] odds = new int[NMAX+1][];
        for(int n = 0; n <= NMAX; n++) {
            odds[n] = new int[n + 1];
        }
        // fill triangular array
        for(int n = 0; n < odds.length; n ++) {
            for(int k = 0; k < odds[n].length; k++) {
                /*
                 * compute binomial coefficient n*(n-1)*(n-2)*(n-3)*...*(n-k+1)/(1*2*3*...*k)
                 */
                int lotteryOdds = 1;
                for(int i = 1;i <= k; i++) {
                    lotteryOdds = lotteryOdds * (n - i +1) / i;
                }
                odds[n][k] = lotteryOdds;
            }
        }
        //print triangular array
        for(int[] row : odds) {
            for(int odd : row)
            {
                System.out.printf("%4d",odd);
            }
            System.out.println("");
        }
    }
}
